Sherlock Holmes
Dr. John H. Watson
Adrea Spedding
Insp. Lestrade
Norman Locke
Radlik
Adam Gilflower
Mrs. Hudson
Larry (uncredited)
Artie - Shooting Gallery Attendant (uncredited)
Fred Garvin (uncredited)
Fortune Teller (uncredited)
Obongo - Pygmy (uncredited)
Charwoman (uncredited)
News Vendor (uncredited)
Carnival Patron (uncredited)
Toy Doll Attendant (uncredited)
Susan (uncredited)
Radio Announcer (uncredited)
Casino Patron (uncredited)
Robert (uncredited)
Doorman (uncredited)
Casino Croupier (uncredited)
Henchman Taylor (uncredited)
Plainclothesman (uncredited)